Field of the Invention
The invention relates to a package and a manufacturing method thereof, and more particularly to a semiconductor package and a manufacturing method thereof.
Description of Related Art
To satisfy the needs for electronic products to be slim and small, semiconductor packages serving as core elements of the electronic products also develop toward miniaturization. Recently in the industry, a miniature semiconductor package such as chip-size package (CSP) has been developed, which is characterized in that a size of the CSP is approximately a size of a chip thereof or slightly larger than the size of the chip thereof. On the other hand, in addition to the miniature size, the semiconductor packages also need to enhance integrity and an amount of input/output terminals (I/O) for electrical connection to external electronic devices such as a circuit board, so as to satisfy the needs for electronic products to have high performance and high processing speed. To be able to arrange more input/output terminals (I/O) on a limited area of an active surface of the chip, wafer-level semiconductor packages such as Wafer-Level Chip-Size Package (WLCSP) is emerged.
Current WLCSP is generally manufactured by first performing a molding process so that a molding compound covers a backside of the chip and a side surface connected to the backside while exposing an active surface opposite to the backside. Then, a re-distribution layer is formed on the molding compound and the active surface of the chip, and the input/output terminals (I/O) on the active surface of the chip are electrically connected to the re-distribution layer. Generally speaking, the molding compound formed via the molding process is thicker, which is unfavorable to the miniaturization of the WLCSP. In addition, since the molding compound has a lower thermal conductivity coefficient and unfavorable heat-dissipating effects, heat generated by the chip is mostly transmitted outside via a re-distribution layer, which has limited heat-dissipating area or heat-dissipating path. Therefore, heat-dissipating efficiency is unfavorable. Under the circumstance that the heat cannot be rapidly transmitted to the outside and is accumulated inside the WLCSP, a warpage may easily occur in the WLCSP.